The gas that the flame uses up during burning is ............................ gas, oxygen, carbon dioxide, The percentage of nitrogen gas in atmospheric air is about, 21%, 87%, The gas whose percentage increases in the air after the candle burns is ........................., nitrogen., carbon dioxide, The liquid that is used to detect the presence of carbon dioxide gas is ..........................., distilled water., limewater., Among the components of atmospheric air are ..........., nitrogen., limewater., Among the tools that are used to check gases, thermometer, gas detector tube, The gas present in the air which the flame uses up to keep burning., carbon dioxide., oxygen, Atmospheric air has a role in burning., true, false, The percentage of carbon dioxide gas in atmospheric air is about 21%, true, false, In gas detector tube, there is one chemical substance used for detecting both carbon dioxide and oxygen gases, true, false

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